Sub Application_Error(ByVal sender As Object, _

 ByVal e As EventArgs)

    ' Get the current time

    Dim CurrentTime As DateTime = DateTime.Now()

    ' Get the stored time of the last error

    Dim LastString As String = Application("LastErrorTime")

    Dim LastTime As DateTime

    Dim SafeTime As DateTime

    ' If there was a last error, figure out when it was

    If Len(LastString) > 0 Then

        LastTime = Convert.ToDateTime(LastString)

        ' TimeSpan(0, 1, 0) = one minute

        ' This calculates a time one minute before "now"

        SafeTime = CurrentTime.Subtract(New TimeSpan(0, 1, 0))

    End If

    ' Only send mail if there was no last error (in

    ' which case the string retrieved from the application

    ' state will be empty) or if it's been at least one

    ' minute since the last mail

    If (Len(LastString) = 0) Or (SafeTime > LastTime) Then

        ' Get the actual error that brought us here

        Dim ex As Exception = _

         Server.GetLastError.InnerException

        ' Create a string with the error information

        Dim Message As StringBuilder = New StringBuilder( _

         "An error occurred in the application:" & vbCrLf)

        Message.Append(ex.Message & vbCrLf)

        Message.Append("Stack trace:" & vbCrLf)

        Dim s As StringBuilder = New StringBuilder(ex.StackTrace)

        Message.Append(s.Replace(" at ", " at " & vbCrLf))

        ' Mail the message to the developer

       SmtpMail.Send("App@sample.com", "Dev@sample.com", _

         "Application Error", Message.ToString())

    End If

    ' Cleanup to do whether we send mail or not

    ' Store the time of this error

    Application("LastErrorTime") = Convert.ToString(CurrentTime)

    ' Clear the error

    Server.ClearError()

    ' Tell the user we're on top of it

    Response.Write("We're sorry, but an unexpected error has occurred")

    Response.End()

End Sub